#include <stdio.h>

#define FEATURE_A
#define FEATURE_B

int main(int argc, char *argv[])
{
#ifdef FEATURE_A
    printf("Feature A is enabled. \n");
#endif

#ifdef FEATURE_B
    printf("Feature B is enabled. \n");
#endif

#ifdef FEATURE_C
    printf("Feature C is enabled. \n");

#endif

#ifndef FEATURE_A
    printf("Feature A is unabled.\n");
#else
    printf("Feature A is enabled in up.\n");
#endif
    return 0;
}